1. Field of the Invention
The present invention relates to patient interface devices used to deliver a flow of breathing gas to a patient. The present invention also relates to maintaining apparatuses and maintaining members for patient interface devices.
2. Description of the Related Art
There are numerous situations where it is necessary or desirable to deliver a flow of breathing gas non-invasively to the airway of a patient, i.e., without intubating the patient or surgically inserting a tracheal tube in their esophagus. For example, it is known to ventilate a patient using a technique known as non-invasive ventilation. It is also known to deliver positive airway pressure (PAP) therapy to treat certain medical disorders, the most notable of which is obstructive sleep apnea (OSA). Known PAP therapies include continuous positive airway pressure (CPAP), wherein a constant positive pressure is provided to the airway of the patient in order to splint open the patient's airway, and variable airway pressure, wherein the pressure provided to the airway of the patient is varied with the patient's respiratory cycle. Such therapies are typically provided to the patient at night while the patient is sleeping.
Non-invasive ventilation and pressure support therapies as just described involve the placement of a patient interface device including a mask component having a soft, flexible cushion on the face of a patient. The mask component may be, without limitation, a nasal mask that covers the patient's nose, a pillows style mask wherein a nasal cushion has nasal prongs that are received within the patient's nares, a nasal/oral mask that covers the nose and mouth, or a full face mask that covers the patient's face. The patient interface device is connected to a gas delivery hose and interfaces the ventilator or pressure support device with the airway of the patient, so that a flow of breathing gas can be delivered from the pressure/flow generating device to the airway of the patient.
It is known to maintain such devices on the face of the patient by way of a headgear having one or more straps adapted to fit over/around the patient's head. Employing headgear straps often results in a feeling of claustrophobia for the patient. For example, the headgear straps typically pull the mask component onto the patient's face, such that the only practical way to remove the mask component is to unfasten the straps.